Determining the structure of confined supercapacitor electrolytes

As electrochemical energy storage devices, electrical double layer (EDL) supercapacitors complement batteries since they are capable of substantially higher power densities. Energy in EDL supercapacitors is stored in the “double layer” of adsorbed ions on high surface area charged electrodes. However, despite its immense importance, the structure of EDL has never been measured in atomistic detail due to a lack of suitable methods. As a result, realistic predictive models for supercapacitors are notoriously absent. To address this, and as a first step towards developing operando studies of supercapacitor electrolyte structure, we will use NIMROD to study the structure of two supercapacitor electrolytes in the bulk and confined in a mesoporous carbon. We will use the power of neutrons to an utilise isotopic H/D substitution, and complimentary data refined simulation analysis, to reveal, in atomistic detail, how the structure of these important liquids changes in the presence of carbon electrode surfaces.